Abstract: It is known that after hydrogenation, the polycyclic aromatic hydrocarbons in DCC light cycle oil and heavy cycle oil can be saturated into naphthenic-aromatic ring structure, which has catalytic cracking performance again. A novel RHT-DCC combined cycle process was developed by SINOPEC Research Institute of Petroleum Processing to produce chemical raw materials from residual oil. In this process residual oil blended with DCC light cycle oil and heavy cycle oil rich in poly-aromatics is co-hydrotreated in RHT unit and then deeply cracked in DCC unit to produce ethylene, propylene, butene and light aromatics, the newly produced DCC light and heavy cycle oils come into the RHT-DCC process again and form an integrated cycle process. Therefore, the combined cycle process of RHT-DCC can greatly improve the yield of low carbon olefins and light aromatic hydrocarbons. The total yield of ethylene, propylene, butene and light aromatics reached 55.01% (based on fresh Kuwait AR feed), far higher than that of conventional non-combined process(42.57%).

Key words: hydrogenation, deep catalytic cracking, combined processed, residue, chemical raw material